An overview of topological materials : From synthesis to applications

The rise of topological materials in the recent years has created a paradigm shift in the fundamental research of condensed matter physics.The materials aspect of the research in this area received emphasis only after the discovery of three dimensional topological insulators and gained a significant pace due to the realization of topological metals in Dirac and Weyl semimetals. In this talk, I will introduce variety of topological states in simple compounds and try to understand their classifications based on crystal symmetry, spin-orbit coupling, magnetic interactionetc. Many of these topological materials show extraordinary transport characteristics like extremely large mobility of electrons, high conductivity and record breaking magnetoresistance. The variety of topological metals go beyond Dirac and Weyl semimetals, which we have studied in the form of triple point Fermionic and sextuple-point Fermionic compounds. Based on theseexcellent electronic properties, I will show that topological semimetals are also ideal candidates for hydrogen evolution catalysis.

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